I think I screwed up my Yubikey. I was poking around in the Personalization Tool, and here's what I did:

1) On the Settings page, I clicked the Update Settings... button.2) Then I clicked on the button for Configuration Slot 1.3) Then clicked the Update button.

I then got a file browser window directing me to select a Log file (in csv format). At this point I had no idea what log file it wanted me to specify, so I just canceled the operation. This put me back on the Settings > Update Yubikey Settings page in the Personalization Tool. Then I just exited out of the tool.

After that, I noticed that the light on my Yubikey stays on, whereas before I did the stuff listed above, the light was normally off when the key was plugged into a USB port. Additionally, the Yubikey authentication failed when trying to log into my Lastpass account.

So to fix the authentication failure, I got back into the Personalization Tool and did the following:

1) Clicked Yubico OTP at the top of the window.2) Clicked the Quick button.3) Clicked on the button for Configuration Slot 1.4) Clicked the Regenerate button.5) Clicked the Write Configuration button and specified an output csv file.6) Clicked the Upload to Yubico button and followed the instructions on the web page to upload the AES key.7) The AES key upload was successful.

After reconfiguring Slot 1, the Yubikey can now successfully log into Lastpass. However, the light now stays on constantly. It didn't do that before I started messing with it. I have two other Yubikeys (the ones I have are the red, green, and white Yubikeys that were sold as a bundle), and these two other keys do not have the light lit up after they are plugged into a USB port. They flash the light once when first plugged in, but then the light goes out. This is the normal behavior.

So here's my question:Why does the light stay on constantly on the key that I messed with? Is this a problem? It still works successfully when logging into my Lastpass account, but the constantly-on light concerns me, as it didn't exhibit that behavior originally. So clearly, something I did has caused it to stay on.

Ideas?

P.S. I've attached a screenshot (below) of the Personalization Tool which shows the Yubikey in question.